Process of making alkali perborates.



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QTTG LIEBKNECHT, OE FBANKKFORT-ON-THEQMAIH, GER-MANY, ASSIGNGE TO THE RDESSLER & HASSLACHEE CHEIltHGAL COMPANY, OF NEW YORK, N. 11, .ii. COR- PORATION OF NEW YORK.

PROCESS OF MAKING ALKALI PERBQRAI'ES.

No Drawing.

To all whom it may concern:

Be it known that I, O'rro Linnnnncrir, a subject of the German Emperor, and resident of Frankfort-on-the-ll/lain, Germany, have invented certain new and useful Improvements in Processes of Making Alkaliof electrolytically produced alkali percarbonate with a, solution of an alkali borate and particularly' a process of making sodium perborate consisting in electrolyzing solu tion of an alkali carbonate and a sodium borate.

According to my application mentioned above, sodium perborate is produced easily, if the work is carried out in the presence of solid perborate of sodium.

I found, however, that there is yet another method affording even greater convenience in manufacturing the alkali-perborate by continuously maintaining the elec trolyte completely saturated with borax and soda; in order to achieve this end, borax and soda must be present in the solid phase.

As to whether, and if so in which Way, the current density affects the yield of perborate in the electrolytic process, I have found that contrary to the experience hitherto gained in the electrolysis of salt solutions to oxidize said salts, the yield increases Within Wide limits by increasing the current density, the yield depending upon a high density of current at the cathode as Well as at the anode.

Specification of Letters Eatent.

Application filed Inlay $3., 1916.

Patented Jan. 8, lit-P18.

Serial no. mean.

in the electrolytic oxidation of salts it has been the universal practice to Work at the anode with a current density which was low as compared with that prevailing at the cathode. As I have found that 1 can improve the yield of pcrborate by applying a high current density at the anode, 1 can of course reduce the surface of the anode so P that my new process works'in the direction of making the current density at the anode approximately equal to that of the cathode.

I claim:

1. The process of making alkaliperborate, consisting in clectrolyzing a substantially saturated solution of an all alicarbonate and alkaliborate with a current density approximately equally high at both the cathode and anor e.

2. The process of making alkaliperborate,

consisting in electrolyzing a substantially- OTTO LIEBKNECHT.

l Vitnesses Jun): Gnuno, lflnnn' Edwin CARLSUN.

Elli 

